Process for the preparation of substituted indenes and their use as ligand systems for metallocene catalysts

ABSTRACT

The invention relates to a process for the preparation of a compound of the formula IV or IVa ##STR1## in which R 1  -R 5  are preferably hydrogen or alkyl, which comprises reacting a compound I ##STR2## with a compound II ##STR3## in which X 1  and X 2  are preferably halogen, to give the corresponding indanones, which are converted into the compounds IV and IVa by reduction and dehydration. The compounds IV and IVa are important intermediate products for the preparation of chiral metallocene complexes which are suitable catalyst components for olefin polymerization.

This application is a continuation of application Ser. No. 08/462,587filed Jun. 5, 1995, which is a continuation of Ser. No. 08/291,738 filedAug. 17, 1994, now abandoned, which is a continuation application ofSer. No. 07/980,993 filed Nov. 24, 1992, now abandoned.

The present invention relates to a simple process for the preparation ofindene derivatives substituted on the five- and six-membered rings.

Compounds of this type are important intermediate products in thepreparation of metallocene complexes. In particular, the correspondingbridged, chiral zirconium derivatives are of great importance as highlyactive catalysts in olefin polymerization (cf. EP-A 129 368). Theproperties of the catalysts can be influenced in a controlled manner byvarying the ligand system, for example by substitution. It is therebypossible to modify the polymer yield, the molecular weight, thetacticity or the melting point of the polymers to the desired extent(New J. Chem. 14 (1990) 499; Organomet. 9 (1990) 3098; Angew. Chem. 102(1990) 339; EP-A 316 155; and EP-A 351 392).

Indenes furthermore can also be employed as monomers inhomopolymerization or copolymerization with other olefins (cf. Macromol.22 (1989) 3824; and Bull. Soc. Chim. Fr. 6 (1969) 2039).

However, the few substituted indenes described in the literature as arule are accessible only in low yields via multi-stage syntheses. Theyare usually obtained from the correspondingly substituted 1-indanones byreduction and subsequent dehydration. The corresponding indanones areobtainable in multi-stage syntheses starting from substituted aromatics(Bull. Soc. Chim. Fr. 6 (1969) 1981; Acta Chem. Scand. B 30 (1976) 527;Austr. J. Chem. 29 (1970) 2572; Chem. Lett. (1981) 729; and Ber. 97(12)(1964) 3461). Certain substitution patterns moreover are not accessibleby this route.

There was the task of discovering a process for the preparation of theabovementioned indenes which avoids the disadvantages known from theprior art. Such indenes allow access to novel metallocene complexes.

It has been found that aromatics of the following formula I react withderivatives of propionic acid carrying a leaving group in the α-positionand with a Friedel-Crafts catalyst to give substituted 1-indanones inhigh yields. This result was completely unexpected, since these productswould have been expected only with derivatives of propionic acid whichcarry a leaving group in the β-position (cf. J. Amer. Chem. Soc. 72(1950) 3286).

Moreover, this synthesis is a one-stage process which is easy to handleindustrially. The indanones can then be converted into the correspondingindenes by known methods. At the same time, the process according to theinvention allows the preparation of novel compounds of the structuretype mentioned.

The present invention therefore relates to a process for the preparationof a compound of the formula IV or an isomer thereof of formula IVa##STR4## in which R¹, R², R³, R⁴ and R⁵ are identical or different andare hydrogen, (C₁ -C₂₀)alkyl, (C₆ -C₁₄)aryl, (C₁ -C₁₀)alkoxy, (C₂-C₁₀)alkenyl, (C₇ -C₂₀)arylalkyl, (C₇ -C₂₀)alkylaryl, (C₆ -C₁₀)aryloxy,(C₁ -C₁₀)-fluoroalkyl, (C₆ -C₁₀)halogenoaryl, (C₂ -C₁₀)alkynyl, aradical --SiR⁶ ₃, in which R⁶ is (C₁ -C₁₀)alkyl, a halogen atom or aheteroaromatic radical which has 5 or 6 ring members and can contain oneor more hetero atoms, or adjacent radicals R¹ -R⁴, with the atomsjoining them, form one or more rings, which comprises reacting acompound of the formula I ##STR5## with a compound of the formula II##STR6## or an anhydride thereof, in the presence of a Friedel-Craftscatalyst to give a compound of the formula III or of the formula IIIa##STR7## in which R¹ -R⁵ have the meanings given and X¹ and X² areidentical or different and are a nucleophilic leaving group, andconverting this into the compound of the formula IV or IVa by reductionand dehydration by known methods.

In these formulae, alkyl is straight-chain or branched alkyl. Halogen isfluorine, chlorine, bromine or iodine, in particular fluorine orchlorine. Examples of heteroaromatic radicals are thienyl, furyl orpyridyl.

The indanones can be obtained in the form of two structural isomers ofthe formula III and IIIa, depending on the substitution pattern on thearomatic radical. These isomers can be reduced, in the pure form or as amixture, with reducing agents such as NaBH₄ or LiAlH₄ by methods whichare known from the literature, to give the corresponding indanols, whichcan then be dehydrated with acids, such as sulfuric acid, oxalic acid orp-toluenesulfonic acid, or by treatment with dehydrating substances,such as magnesium sulfate, sodium sulfate, aluminum oxide, silica gel ormolecular sieves, to give indenes of the formula IV or IVa (Bull. Soc.Chim. Fr. 11 (1973) 3092; Organomet. 9 (1990) 3098 and the embodimentexamples).

X¹ and X² are preferably a halogen atom, a hydroxyl group, a tosyl groupor a (C₁ -C₁₀)alkoxy group; in particular a halogen atom, particularlypreferably bromine or chlorine.

Suitable Friedel-Crafts catalysts are, for example, AlCl₃, AlBr₃, FeCl₃,SbCl₅, SnCl₄, BF₃, TiCl₄, ZnCl₂, HF, H₂ SO₄, polyphosphoric acid, H₃ PO₄or an AlCl₃ /NaCl melt; in particular AlCl₃.

In the formulae IV and IVa, preferably,

R¹, R², R³ and R⁴ are identical or different and are hydrogen, (C₁-C₁₀)alkyl, (C₆ -C₁₄)aryl, (C₁ -C₄)alkoxy, (C₂ -C₆)alkenyl, (C₁C₆)fluoroalkyl, a halogen atom or a heteroaromatic radical which has 5or 6 ring members and can contain one or more hetero atoms, or adjacentradicals R¹ -R⁴, with the atoms joining them, form a ring, and R⁵ is(C_(l) -C₁₀)alkyl.

In particular,

R¹, R², R³ and R⁴ are identical or different and are hydrogen or (C₁-C₁₀)alkyl, or the radicals R¹ and R² or R³ and R⁴, with the atomsjoining them, form a ring, and R⁵ is methyl.

The starting compounds of the formulae I and II are known and arecommercially obtainable, or they can be prepared by processes which areknown from the literature.

The reaction is carried out in an inert solvent. Methylene chloride orCF₂ is preferably employed. If the starting components are liquid, asolvent can also be dispensed with.

The molar ratios of the starting compounds, including the Friedel-Craftscatalyst, can vary within wide limits. The molar ratio of compoundI:II:catalyst is preferably 1:0.5-1.5:1.5; in particular 1:1:2.5-3.

The reaction temperature is preferably 0° C. to 130° C., in particular25° C. to 80° C.

The reaction times as a rule vary between 30 minutes and 100 hours,preferably between 2 hours and 30 hours.

Preferably, a mixture of compounds I and II is initially introduced intothe reaction vessel and the Friedel-Crafts catalyst is metered in. Thereverse sequence of addition is also possible.

The indanones of the formula III or IIIa can be purified bydistillation, column chromatography or by crystallization.

The substituted indenes can be obtained as double bond isomers (IV/IVa).These can be purified from by-products by distillation, columnchromatography or crystallization.

The process according to the invention is distinguished in particular inthat variously substituted indenes can be obtained in a high yield in asimple and short synthesis. The substitution pattern on the five- andsix-membered ring can be varied within a very wide range in thisprocess. This means that novel indene derivatives are also accessible.

The present invention furthermore relates to the use of the indenederivatives IV/IVa as an intermediate product in the preparation ofmetallocene complexes, in particular of those of the following formulaVI.

The metallocenes of the formula VI are novel and the present inventionlikewise relates to them. ##STR8## in which M¹ is titanium, zirconium,hafnium, vanadium, niobium or tantalum,

R¹, R², R³, R⁴ and R⁵ are identical or different and are hydrogen, (C₁-C₂₀)alkyl, (C₆ -C₁₄)aryl, (C₁ -C₁₀)alkoxy, (C₂ -C₁₀)alkenyl, (C₇-C₂₀)arylalkyl, (C₇ -C₂₀)alkylaryl, (C₆ -C₁₀)aryloxy, (C₁-C₁₀)fluoroalkyl, (C₆ -C₁₀)halogenoaryl, (C₂ -C₁₀)alkynyl, a radical--SiR⁶ ₃, in which R⁶ is (C₁ -C₁₀)alkyl, a halogen atom or aheteroaromatic radical which has 5 or 6 ring members and can contain oneor more hetero atoms, or adjacent radicals R¹ -R⁴, with the atomsjoining them, form one or more rings,

R⁷ is a radical

in which ##STR9## M² is carbon, silicon, germanium or tin, R⁸ and R⁹ areidentical or different and are hydrogen, (C₁ -C₂₀)alkyl, (C₆ -C₁₄)aryl,(C₁ -C₁₀)alkoxy, (C₂ -C₁₀)alkenyl, (C₇ -C₂₀)arylalkyl, (C₇-C₂₀)alkylaryl, (C₆ -C₁₀)aryloxy, (C₁ -C₁₀)fluoroalkyl, (C₆-C₁₀)halogenoaryl, (C₂ -C₁₀)alkynyl or halogen, or

R⁸ and R⁹, together with the atom joining them, form a ring, p is 0, 1,2 or 3 and

R¹⁰ and R¹¹ are identical or different and are hydrogen, (C₁ -C₁₀)alkyl,(C₁ -C₁₀)alkoxy, (C₆ -C₁₀)aryl, (C₆ -C₁₀)aryloxy, (C₂ -C₁₀)alkenyl, (C₇-C₄₀)arylalkyl, (C₇ -C₄₀)alkylaryl, (C₈ -C₄₀)arylalkenyl, hydroxyl or ahalogen atom.

Preferably,

M¹ is zirconium or hafnium, in particular zirconium,

R¹, R², R³ and R⁴ are identical or different and are hydrogen, (C₁-C₁₀)alkyl, (C₆ -C₁₄)aryl, (C₁ -C₄)alkoxy, (C₂ -C₆)alkenyl, (C₁-C₆)fluoroalkyl, a halogen atom or a heteroaromatic radical which has 5or 6 ring members and can contain one or more hetero atoms, and R⁵ is(C₁ -C₁₀)alkyl, or adjacent radicals R¹ -R⁴, with the atoms joiningthem, form a ring,

M² is carbon or silicon, in particular silicon, R⁸ and R⁹ are identicalor different and are hydrogen, (C₁ 14 C₆)alkyl, (C₆ -C₁₀)aryl, (C₁-C₆)alkoxy, (C₂ -C₄)alkenyl, (C₇ -C₁₀)arylalkyl or (C₇ -C₁₀)alkylaryl,or R⁸ and R⁹, together with the atom joining them, form a ring, p is 1or 2, preferably 1, and R¹⁰ and R¹¹ are identical or different and arehydrogen, (C₁ -C₃)alkyl, in particular methyl, (C₁ -C₃)alkoxy, (C₆-C₈)aryl, (C₆ -C₈)aryloxy, (C₂ -C₄)alkenyl, (C₇ -C₁₀)arylalkyl, (C₇-C₁₀)alkylaryl, (C₈ -C₁₂)arylalkenyl or a halogen atom, preferablychlorine.

Preferably, the radicals R¹⁰ and R¹¹ are identical and are chlorine ormethyl. M² is, in particular, silicon, and the radicals R⁸ and R⁹ areidentical or different and are preferably (C₁ -C₆)alkyl, preferablymethyl, or (C₆ -C₁₀)aryl.

Furthermore, for the compounds of the formula VI, R⁵ and R³ ; R¹, R³ andR⁵ ; R¹, R², R³ and R⁵ or all the radicals R¹ -R⁵ are preferably otherthan hydrogen and are preferably (C₁ -C₄)alkyl. Particularly preferably,the radicals R¹, R³ and R⁵ are other than hydrogen, are identical ordifferent and are (C₁ -C₄)alkyl.

The preferred substitution patterns on the indenyl radicals aretherefore 2,6-, 2,4,6-, 2,4,5-, 2,4,5,6- and 2,4,5,6,7-, in particular2,4,6- and 2,4,5-. The 2-position here on the indenyl radicals (R⁵) ispreferably substituted by a methyl group. Furthermore, for the compoundsof the formula VI, the indenyl radicals are benzo-fused.

The compounds VI mentioned in the embodiment examples are of particularimportance.

Starting from the indenes of the formulae IV and IVa, which can beemployed as an isomer mixture, the preparation of the metallocenes VIproceeds by processes which are known from the literature (cf.AU-A-31478/89, J. Organomet. Chem. 342 (1988) 21, EP-A 284 707 and theembodiment examples) in accordance with the following equation:##STR10## (X³ =a nucleophilic leaving group, such as, for example, Cl,Br or O-tosyl).

The metallocene halides of the formula VI can be derivatized by methodswhich are known from the literature, for example by reactions withalkylating agents, such as lithiumalkyls, to give the correspondingmono- or dialkyl compounds (J. Amer. Chem. Soc. 95 (1973) 6263).

The bridged ligand systems of the formula V can be obtained asstructural isomers, depending on the substitution pattern of the indene.If these isomers are not separated, structural isomers of metallocenesof the formula VI are formed. The metallocenes of the formula VI areobtained as a mixture of the racemic form with the meso form. Theseparation of the isomeric forms, in particular the removal of the mesoform, which is undesirable for the olefin polymerization, is known inprinciple (AU-A-31478/89; J. Organomet. Chem. 342 (1988) 21; and EP-A284 707). It is as a rule carried out by extraction or recrystallizationusing various solvents.

The present invention furthermore relates to the use of the compounds ofthe formula VI as catalyst components in olefin polymerization.

The metallocenes VI are highly active catalysts and are suitable, forexample, for the preparation of olefin polymers of high isotacticity andhigh molecular weight.

The polymerization or copolymerization is carried out in a known mannerin solution, in suspension or in the gas phase, continuously ordiscontinuously, in one or more stages, at a temperature of 0 to 150°C., preferably 30 to 80°C. Olefins of the formula R^(a) --CH═CH--R^(b)are polymerized or copolymerized. In this formula, R^(a) and R^(b) areidentical or different and are a hydrogen atom or an alkyl radicalhaving 1 to 14 carbon atoms. However, R^(a) and R^(b), with the carbonatoms joining them, can also form a ring. Examples of such olefins areethylene, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene,norbornene, dimethaneoctahydronaphthalene or norbornadiene. Inparticular, propylene and ethylene are polymerized (cf., for example,EP-A 129 368).

Aluminoxanes are preferably used as cocatalysts (cf. EP-A 129 368;Polyhedron 9 (1990) 429 and the embodiment examples).

According to the invention, instead of or in addition to an aluminoxane,compounds of the formulae R_(x) NH_(4-x) BR'₄, R_(x) PH_(4-x) BR'₄, R₃CBR'₄ or BR'₃ can be used as suitable co-catalysts. In these formulae, xis a number from 1 to 4, preferably 3, the radicals R are identical ordifferent, preferably identical, and are C₁ -C₁₀ -alkyl or C₆ -C₁₈-aryl, or two radicals R, together with the atom joining them, form aring, and the radicals R' are identical or different, preferablyidentical, and are C₆ -C₁₈ -aryl, which can be substituted by alkyl,haloalkyl or fluorine (EP-A 277 003, 277 004, 426 638 and 427 697).

The following examples serve to illustrate the invention in more detail.

EXAMPLE A 2,5,7-Trimethyl-1-Indanone (1)

107 g (810 mmol) of AlCl₃ are slowly added to a solution of 34.4 g (324mmol) of m-xylene (99% pure) and 74 g (324 mmol) of 2-bromoisobutyrylbromide (98% pure) in 600 ml of analytical grade methylene chloride viaa solids metering funnel at room temperature, while stirring vigorously,whereupon vigorous evolution of gas started. The mixture was stirred atroom temperature for 15 hours, poured onto ice-water, which wasacidified with 25 ml of concentrated HCl and extracted several timeswith ether. The combined organic phases were washed first with asaturated NaHCO₃ solution and then with a saturated NaCl solution anddried with magnesium sulfate. The oil which remained after the solventhad been stripped off under reduced pressure was distilled over a shortdistillation bridge. 52.4 g of the indanone 1 passed over at 81-90°C./0.1-0.2 mbar in the form of a colorless oil which crystallized atroom temperature. The yield was 93%.

¹ H-NMR spectrum (100 MHz, CDCl₃): 7.05 (1,s), 6.87 (1,s), 3.25 (1,q),2.43-2.80 (2,m), 2.57 (3,s), 2.35 (3,s), 1.25 (3,d).

Mass spectrum: 174 M⁺, correct disintegration pattern.

EXAMPLE B 2,4,6-Trimethylindene (2)

20.4 g (117 mmol) of 2,5,7-trimethyl-1-indanone (1) were dissolved in300 ml of a mixture of tetrahydrofuran/methanol (2:1), and 6.6 g (175mmol) of NaBH₄ were added at room temperature. The mixture was stirredfor a further hour, 50 ml of half-concentrated HCl were added and themixture was extracted with ether. The combined organic phases were driedover sodium sulfate and freed from the solvent. The residue wastransferred to a distillation apparatus, and 13 g of magnesium sulfatewere added. A vacuum of about 10 mbar was applied and the mixture washeated up until the product distilled over (130-150° C.). Distillationgave 17.7 g of the indene 2 as a colorless oil. The yield was 96%.

¹ H-NMR spectrum (100 MHz, CDCl₃): double bond isomers A:B=2:1

Isomer A: 6.97 (1,s), 6.80 (1,s), 6.50 (1,m), 3.20 (2,m), 2.1-2.3 (9,m).

Isomer B: 6.87 (1,s), 6.70 (1,s), 6.37 (1,m), 3.07 (2,m), 2.1-2.3 (9,m).

Mass spectrum: 158 M⁺, correct disintegration pattern.

EXAMPLE C 2-Methyl-5,7-Diisopropyl-1-Indanone (3) and2-Methyl-4,6-Diisopropyl-1-Indanone (3a)

174 g (1300 mmol) of AlCl₃ were slowly added to a solution of 84.8 g(523 mmol) of 1,3-diisopropylbenzene and 120 g (523 mmol) of2-bromoisobutyryl bromide (98% pure) in 600 ml of analytical grademethylene chloride via a solids metering funnel at room temperature. Themixture was heated under reflux for a further 20 hours and then workedup analogously to Example A. The crude product was chromatographed on 3kg of silica gel 60. The indanones 3 and 3a were able to be elutedseparately with a mobile phase mixture of hexane/15% ethyl acetate.Using the same mobile phase, the compound2-methyl-5-isopropyl-1-indanone followed as a by-product in a furtherzone. However, separation of the two isomers is not necessary for thefurther reactions. The overall yield was 93 g (78%).

¹ H-NMR spectrum (360 MHz, CDCl₃): isomer mixture (3:2) 7.49 (d), 7.36(d), 7.13 (s), 7.10 (s), 4.15 (septet), 3.25-3.40 (m), 3.10 (septet),2.90-3.00 (m), 2.60-2.73 (m), 1.22-1.30 (m).

Mass spectrum: 230 M⁺, correct disintegration pattern.

EXAMPLE D 2-Methyl-4,6-Diisopropylindene (4) and2-Methyl-5,7-Diisopropylindene (4a), Variant I

19.3 g (511 mmol) of NaBH₄ were added to a solution of 78.5 g (341 mmol)of the isomer mixture 3/3a in 700 ml of a solvent mixture oftetrahydrofuran/analytical grade methanol (2:1) at room temperature.After the mixture had been stirred at room temperature for 2 hours,120-130 ml of half-concentrated HCl were added and the mixture wasextracted with ether. The combined organic phases were dried with Na₂SO₄. The residue which remained after the solvent had been stripped offwas taken up in 500 ml of methylene chloride, and the mixture was heatedunder reflux with 6.5 g (34 mmol) of p-toluenesulfonic acid for 15minutes. The residue which remained after the solvent had been strippedoff was chromatographed on 1.5 kg of silica gel 60. Using a mobile phasemixture of hexane/diisopropyl ether 20:1, 56 g of the isomer mixture4/4a were able to be isolated in the form of a colorless oil. Theoverall yield was 86%.

¹ H-NMR spectrum (100 MHz, CDCl₃): double bond isomers (1:1) 7.1 (m),6.95 (m), 6.60 (m), 6.43 (m), 3.25 (br), 2.75-3.20 (m), 2.12 (d), 1.28(d), 1.25 (d).

Mass spectrum: 214 M⁺, correct disintegration pattern.

EXAMPLE E 2-Methyl-4,6-Diisopropylindene (4) and2-Methyl-5,7-Diisopropylindene (4a), Variant II

19.3 g (511 mmol) of NaBH₄ were added to a solution of 78.5 g (341 mmol)of the isomer mixture 3/3a in 700 ml of a solvent mixture oftetrahydrofuran/analytical grade methanol (2:1). After the mixture hadbeen stirred at room temperature for 2 hours, 120-130 ml ofhalf-concentrated HCl were added and the mixture was extracted withether. The combined organic phases were dried with Na₂ SO₄. The residuewhich remained after the solvent had been stripped off was transferredto a distillation apparatus, and 50 mg of magnesium sulfate were added.After a vacuum of about 1 mbar had been applied, the mixture was heatedup until the product passed over (about 130° C.). 65 g of the isomermixture 4/4a were obtained as a colorless oil. The yield was 90%.

EXAMPLE F 2-Methyl-1-Indanone (5)

17.3 g (125 mmol) of AlCl₃ were added to a solution of 3.91 g (50 mmol)of benzene in 30 ml of analytical grade methylene chloride, whilecooling with ice. 11.9 g (52 mmol) of 2-bromoisobutyryl bromide werethen added, and stirring was continued at 0° C. for 1 hour and at roomtemperature for 2 hours. The mixture was heated under reflux for afurther 15 hours and then worked up analogously to Example A. The crudeproduct was chromatographed on 100 g of silica gel (hexane/methylenechloride 1:1). The yield was 5.1 g (70%).

¹ H-NMR spectrum (100 MHz, CDCl₃): 7.5 (m), 3.33 (q), 2.73 (m), 1.30(d).

Mass spectrum: 146 M⁺, correct disintegration pattern.

EXAMPLE G 2-Methylindene (6)

Analogously to Example D, 5.0 g (34 mmol) of 2-methyl-1-indanone (5)were reduced with 1.94 g (51 mmol) of NaBH₄. The alcohol, which was notpurified further, was then further reacted in the presence of 0.2 g ofp-toluenesulfonic acid in 100 ml of toluene at 80° C. Chromatography on100 g of silica gel (hexane/methylene chloride 9:1) gave 3.68 g (82%) of2-methylindene (6).

¹ H-NMR spectrum (100 MHz, CDCl₃): 7.2 (4,m), 6.45 (1,m), 3.25 (2,m),2.1 (3,m).

Mass spectrum: 130 M⁺, correct disintegration pattern.

EXAMPLE H 2-Methyl-5-Isobutyl-1-Indanone (7)

17.3 g (125 mmol) of AlCl₃ were added to a solution of 6.71 g (50 mmol)of isobutylbenzene in 30 ml of analytical grade methylene chloride,while cooling with ice. 11.9 g (52 mmol) of 2-bromoisobutyryl bromidewere then added rapidly, and stirring was continued at 0° C. for 1 hourand at room temperature for 2 hours. The mixture was heated under refluxfor a further 15 hours and then worked up analogously to Example A. Thecrude product was chromatographed on 100 g of silica gel(hexane/methylene chloride 1:1). The yield was 8.42 g (83%).

¹ H-NMR spectrum (100 MHz, CDCl₃): 7.7 (m), 7.2 (m), 3.35 (q), 2.70 (m),2.58 (d), 1.95 (q), 1.25 (d), 0.93 (d).

Mass spectrum: 202 M⁺, correct disintegration pattern.

EXAMPLE J 2-Methyl-6-Isobutylindene (8)

Analogously to Example D, 8.3 g (41 mmol) of2-methyl-5-isobutyl-1-indanone (7) were reduced with 2.4 g (62 mmol) ofNaBH₄. The alcohol, which was not purified further, was then furtherreacted in the presence of 0.4 g of p-toluenesulfonic acid in 100 ml oftoluene at 80° C. Chromatography on 400 g of silica gel (hexane) gave7.17 g (95%) of 2-methyl-6-insobutylindene (8).

¹ H-NMR spectrum (100 MHz, CDCl₃): 7.1 (m), 6.45 (m), 3.25 (m), 2.45(d), 2.88 (q), 2.10 (d), 0.95 (d).

Mass spectrum: 184 M⁺, correct disintegration pattern.

EXAMPLE K 2,5,6,7-Tetramethyl-1-Indanone (9)

17.3 g (125 mmol) of AlCl₃ were added to a solution of 6.01 g (50 mmol)of 1,2,3-trimethylbenzene in 30 ml of analytical grade methylenechloride, while cooling with ice. 11.9 g (52 mmol) of 2-bromoisobutyrylbromide were then added rapidly, and stirring was continued at 0° C. for1 hour and at room temperature for 2 hours. The mixture was kept at roomtemperature for a further 15 hours and then worked up analogously toExample A. The crude product was purified by distillation (0.05 mmHg/96-107° C.). The yield was 8.1 g (86%).

¹ H-NMR spectrum (100 MHz, CDCl₃): 7.0 (m), 3.20 (q), 2.60 (m), 2.20(m), 1.25 (d).

Mass spectrum: 188 M⁺, correct disintegration pattern.

EXAMPLE L 2,4,5,6-Tetramethylindene (10)

Analogously to Example D, 1.50 g (8 mmol) of2,5,6,7-tetramethyl-1-indanone (9) were reduced with 0.45 g (12 mmol) ofNaBH₄. The alcohol, which was not purified further, was then furtherreacted in the presence of 0.1 g of p-toluenesulfonic acid in 100 ml oftoluene. Chromatography on 100 g of silica gel (hexane/methylenechloride 9:1) gave 0.88 g (65%) of 2,4,5,6-tetramethylindene (10).

¹ H-NMR spectrum (100 MHz, CDCl₃): 7.0 (s), 6.45 (m), 3.25 (m), 2.60(m), 2.20 (m), 2.10 (d). Mass spectrum: 170 M⁺, correct disintegrationpattern.

EXAMPLE M Dimethylbis (2-Methyl-4,6-Diisopropylindenyl)Silane (11)

9.2 ml (22.8 mmol) of a 2.5 M butyllithium solution in hexane were addedto a solution of 4.9 g (22.8 mmol) of the isomer mixture 4/4a in 25 mlof tetrahydrofuran at 0° C. under Ar as an inert gas, and the mixturewas heated under reflux for a further hour. The red solution was thenadded dropwise to a solution of 1.5 g (11.4 ml) ofdimethyldichlorosilane in 10 ml of tetrahydrofuran, and the mixture washeated under reflux for 8 hours. The batch was poured onto ice-water andextracted with ether. The ether phase was dried over magnesium sulfateand evaporated under reduced pressure. The yellowish oil which remainedwas then chromatographed on 500 g of silica gel 60. With a mobile phasemixture of hexane/5% methylene chloride, 1.4 g of the indene mixture4/4a were able to be eluted first. The ligand system 11 followed withhexane/8% methylene chloride. The viscous oil which remained after themobile phase had been stripped off was able to be crystallized bystirring with methanol in an ice bath. 3.1 g of a yellowish solid wereobtained. The yield was 56%, or 84% with respect to the indene reacted.

¹ H-NMR spectrum (100 MHz, CDCl₃): double bond isomers (3:1) 6.82-7.32(m), 6.70 (m), 6.62 (m), 6.52 (m), 3.75 (s,br), 3.65 (s,br), 3.35 (s),2.70-3.30 (m), 2.05-2.25 (m), 1.10-1.45 (m), 0.10-0.22 (m), -0.15 to-0.32 (m). Mass spectrum: 484 M⁺, correct disintegration.

EXAMPLE NDimethylsilanediylbis(2-Methyl-4,6-Diisopropylindenyl)ZirconiumDichloride (12)

6.3 ml (16.2.mmol) of a 2.5 M butyllithium solution in hexane were addedto a solution of 3.1 g (6.5 mmol) of the ligand system 11 in 25 ml ofdiethyl ether at room temperature under Ar as the inert gas, and themixture was stirred overnight. After addition of 10 ml of hexane, thebeige-colored suspension was filtered and the residue was washed with 20ml of hexane. The dilithium salt was dried under an oil-pump vacuum fora long time and then added to a suspension of 1.6 g (6.8 mmol) of ZrCl₄in 30 ml of methylene chloride at -78° C. The mixture was warmed to roomtemperature in the course of 1 hour and stirred at this temperature fora further 30 minutes. After the solvent had been stripped off, theorange-brown residue was extracted with 50 ml of hexane. After thesolvent had been stripped off, 2.6 g (60%) of the complex 12 wereobtained in the form of a yellow powder. The ratio of the racemate tothe meso form was 3:1. 1.3 g (30%) of the complex 12 were able to beobtained as the pure racemate by recrystallization from hexane (yellowcrystalline powder).

¹ H-NMR spectrum (100 MHz, CDCl₃): 7.27 (2,s,aromatic-H), 7.05(2,s,aromatic-H), 6.80 (2,s,β-Ind-H), 2.6-3.2 (4,m,i-Pr--CH), 2.22(6,s,Ind-CH₃), 1.15-1.40 (30,m, i-Pr--CH₃, Si--CH₃). Mass spectrum: 642M⁺ (with respect to ⁹⁰ Zr), correct isotope pattern, correctdisintegration.

EXAMPLE O Dimethylbis(2,4,6-Trimethylindenyl)silane (13)

25.5 ml (63.7 mmol) of a 2.5 M butyllithium solution in hexane wereadded to a solution of 10.1 g (64 mmol) of the indene 2 in 50 ml oftetrahydrofuran at room temperature under Ar as the inert gas, and themixture was heated under reflux for 1 hour. The solution thus obtainedwas added dropwise to a solution of 4.1 g (32 mmol) ofdimethyldichlorosilane in 20 ml of tetrahydrofuran, and the mixture washeated under reflux for 3 hours. The reaction mixture was poured ontoice-water and extracted several times with ether. The combined organicphases were dried over sodium sulfate and evaporated under reducedpressure. The residue was chromatographed on 450 g of silica gel 60.With a mobile phase mixture of hexane/5% methylene chloride, 2.5 g ofthe indene 2 were able to be eluted first. 6.5 g of the ligand system 13(isomers) followed with hexane/8% methylene chloride. The yield was 54%,or 72% with respect to the indene 2 reacted.

EXAMPLE P Dimethylsilanediylbis(2,4,6-Trimethylindenyl)Zirconiumdichloride (14)

6.6 ml (16.2 mmol) of a 2.5 M butyllithium solution in hexane were addedto a solution of 2.0 g (5.4 mmol) of the ligand system 13 in 30 ml ofdiethyl ether at room temperature under Ar as the inert gas, and themixture was stirred at this temperature for 5-6 hours. The solution wasevaporated completely. The solid residue which remained was washed inportions with a total of 30 ml of hexane and dried under an oil-pumpvacuum for a long time. The beige-colored powder thus obtained was addedto a suspension of 1.23 g (5.5 mmol) of zirconium tetrachloride in 30 mlof methylene chloride at -78° C. After being warmed to room temperature,the reaction mixture was evaporated completely and the residue was driedunder an oil-pump vacuum. The solid residue comprised a mixture of theracemic form with the meso form in a ratio of 1:1. This was first washedwith a small amount of hexane. It was then extracted with a total of 120ml of toluene. The solution was concentrated, and the residue was leftto crystallize at -35° C. 800 mg (28%) of the zirconocene 14 were ableto be obtained as the pure racemate in the form of orange-coloredcrystals.

¹ H-NMR spectrum of the racemate (100 MHz, CDCl₃): 7.20(s,2,aromatic-H), 6.97 (s,2,aromatic-H), 6.70 (s,2,β-Ind-H), 2.32(s,6,CH₃), 2.27 (s,6,CH₃), 2.20 (s,6,CH₃), 1.27 (s,6,Si--CH₃).

Mass spectrum: 530 M⁺ (with respect to ⁹⁰ Zr), correct isotope pattern,correct disintegration.

EXAMPLE R Methylphenylbis(2-Methyl-4,6-Diisopropylindenyl)Silane (15)

18.6 ml (46 mmol) of a 2.5 M butyllithium solution in hexane were addedto a solution of 10 g (46 mmol) of the indene 4/4a in 200 ml oftetrahydrofuran at room temperature under Ar as the inert gas, and themixture was heated under reflux for 1 hour. The solution was addeddropwise to a solution of 4.48 g (23 mmol) of methylphenyldichlorosilanein 30 ml of tetrahydrofuran at room temperature, and the mixture washeated under reflux for 3 hours. The mixture was poured onto ice-waterand extracted several times with ether. The combined organic phases weredried with sodium sulfate and evaporated. The residue waschromatographed on 450 g of silica gel 60. With a mobile phase mixtureof hexane/methylene chloride (10:1), 1.9 g of unreacted indene 4/4a wereable to be recovered first. 7.4 g of the ligand system 15 (isomermixture) then followed. The yield was 57%, or 73% with respect to theindene reacted.

EXAMPLE S Methylphenylsilylbis(2-Methyl-4,6-Diisopropylindenyl)ZirconiumDichloride (16)

11.2 ml (28 mmol) of a 2.5 M butyllithium solution in hexane were addedto a solution of 7.4 g (13.5 mmol) of the ligand system 15 in 30 ml ofdiethyl ether at room temperature under Ar as the inert gas, and themixture was stirred at room temperature for 16 hours. After the solventhad been stripped off, the residue which remained was dried at 40-50° C.for 3-4 hours, and then added to a suspension of 3.2 g (13.5 mmol) ofzirconium tetrachloride in 40 ml of methylene chloride at -78° C. Afterthe mixture had been warmed to room temperature, the solvent wasstripped off under reduced pressure. The solid residue which remainedwas dried under an oil-pump vacuum and extracted with 100 ml of hexane.After the solvent had been stripped off, 5.4 g (55%) of the zirconocene16 were obtained as a mixture of the racemic form with the meso form ina ratio of 2:1 (orange-brown crystalline powder). The pure racemic formis obtainable by recrystallization from hexane.

¹ H-NMR spectrum of the isomer mixture (100 MHz, CDCl₃): 6.6-8.2(m,aromatic-H,β-Ind-H), 2.5-3.2 (m,i-Pr--H), 2.52 (s,CH₃), 2.32 (s,CH₃),2.20 (s,CH₃), 1.90 (s,CH₃), 1.0-1.5 (m,i-Pr--CH₃,Si--CH₃).

Mass spectrum: 704 M⁺ (with respect to ⁹⁰ Zr), correct isotope pattern,correct disintegration.

EXAMPLE T 1,2-Bis(2-Methyl-4,6-Diisopropylindenyl)Ethane (17)

18.6 ml (46 mmol) of a 2.5 M butyllithium solution in hexane were addedto a solution of 5.0 g (23.3 mmol) of the indene 4/4a in 50 ml oftetrahydrofuran at room temperature under Ar as the inert gas, and themixture was heated under reflux for 1 hour. The solution was added to asolution of 2.18 g (11.0 mmol) of 1,2-dibromoethane at -78° C. Thesolution was warmed slowly to room temperature and stirred at thistemperature overnight. The mixture was poured onto ice-water andextracted several times with ether. The combined organic phases weredried with sodium sulfate and evaporated. The residue waschromatographed on 450 g of silica gel 60. With a mobile phase mixtureof hexane/methylene chloride (20:1 to 10:1), 1.2 g of unreacted indene4/4a were able to be recovered first. 1.7 g of the ligand system 17(colorless solid) then followed. The yield was 35%, or 45% with respectto the indene reacted.

EXAMPLE U 1,2-Ethanediylbis(2-Methyl-4,6-Diisopropylindenyl)ZirconiumDichloride (18)

3.5 ml (8.8 mmol) of a 2.5 M butyllithium solution in hexane were addedto a solution of 1.6 g (3.52 mmol) of the ligand system 17 in 20 ml ofdiethyl ether at room temperature under Ar as the inert gas, and themixture was stirred overnight. The residue which remained after thesolvent had been stripped off was washed with hexane and dried under anoil-pump vacuum for a long time. The powder thus obtained was added to asuspension of 815 mg (3.5 mmol) of zirconium tetrachloride in 15 ml ofmethylene chloride at -78° C. After the mixture had been warmed to roomtemperature, it was stirred for a further hour, and the solvent wasremoved under reduced pressure. The residue was dried under an oil-pumpvacuum and extracted with toluene. Stripping off the solvent and washingwith hexane gave 1.5 g (70%) of the zirconocene 18 as a mixture of theracemic with the meso form in a ratio of 2:1 (orange-colored powder).700 mg (32%) of the pure racemate were able to be obtained byrecrystallization from a toluene/hexane mixture.

¹ H-NMR spectrum of the racemate (100 MHz, CDCl₃): 7.3 (s,aromatic-H),7.0 (s,aromatic-H), 6.55 (s,β-Ind-H), 3.6 (s,C₂ H₄), 2.6-3.2(m,i-Pr--H), 2.2 (s,CH₃).

Mass spectrum: 612 M⁺ (with respect to ⁹⁰ Zr), correct isotope pattern,correct disintegration.

EXAMPLE V 2-Methyl-6,7-Benzoindan-1-one (19a) and2-Methyl-4,5-Benzoindan-1-one (19b)

27.5 g (207 mmol) of AlCl₃ were added to a solution of 10 g (83 mmol) ofnaphthalene and 19 g (83 mmol) of 2-bromoisobutyryl bromide in 200 ml ofCH₂ Cl₂ via a solids metering funnel at room temperature in the courseof 30 minutes. After 4 hours, the mixture was worked up analogously toExample A. The crude product was filtered with ethyl acetate over ashort column filled with silica gel. After the solvent had been strippedoff, 15.5 g (95%) of the isomer mixture 19a/19b were obtained as ayellowish oil. The isomer ratio of 19a:19b was 1:2.

¹ H-NMR spectrum (100 MHz, CDCl₃): 19a: 9.15 (m,1H), 7.40-8.10 (m5H),3.47 (dd,1H), 2.62-2.95 (m,2H), 1.37 (d,3H); 19b:7.4-8.0 (m,6H), 3.7(dd,1H), 2.75-3.10 (m,2H), 1.40 (d,3H).

Mass spectrum: 196 M⁺, correct disintegration pattern.

EXAMPLE W 2-Methyl-6,7-Benzoindan-1-One (19a)

The same batch size as in Example V was chosen. The naphthalene wasinitially introduced into the reaction vessel together with the AlCl₃ inCH₂ Cl₂, and bromoisobutyryl bromide was slowly added dropwise at roomtemperature. After 1.5 hours, the mixture was worked up as in Example V.Chromatography on silica gel 60 with a hexane/ethyl acetate mixture gave11 g (67%) of the indanone 19a.

EXAMPLE X 2-Methyl-4,5-Benzoindene (20a) and 2-Methyl-6,7-Benzoindene(20b)

2.2 g (59.5 mmol) of sodium borohydride were added in portions to asolution of 7.8 g (39.7 mmol) of the isomer mixture of the indanones19a/19b (Example V) in 400 ml of a tetrahydrofuran/methanol mixture(2:1) at room temperature, and the mixture was stirred for 14 hours. Thesolution was poured onto ice-water acidified with HCl, and extractedwith ether. The combined organic phases were washed several times withwater and dried with sodium sulfate. The orange-colored oil whichremained after the solvent had been stripped off was dissolved in 240 mlof toluene, and the solution was heated at 80° C. with 570 mg (3.15mmol) of p-toluenesulfonic acid for 15 minutes. The solution was washedseveral times with water at room temperature, dried with sodium sulfateand evaporated. The residue was chromatographed on 300 g of silica gel60. With a mobile phase mixture of hexane/diisopropyl ether (20:1), 4.7g (65%) of the isomer mixture of the indenes 20a/20b in a ratio of 1:2were able to be eluted (colorless oil).

¹ H-NMR spectrum (360 MHz, CDCl₃): isomer mixture 7.2-8.1 (m), 7.05 (m),6.57 (m), 3.57 (s), 3.42 (m), 2.25 (d), 2.20 (d).

Molecular weight: 180 M⁺, correct disintegration pattern.

EXAMPLE Y

Dimethylbis(2-Methyl-4,5-Benzoindenyl)Silane (21)

10.2 ml (25.5 mmol) of a 2.5 M butyllithium solution in hexane wereadded to a solution of 4.6 g (25.5 mmol) of the isomer mixture of theindenes 20a/20b (Example X) in 50 ml of tetrahydrofuran at roomtemperature, and the mixture was heated under reflux for 1 hour. The redsolution was then added dropwise to a solution of 1.55 g (12 mmol) ofdimethyldichlorosilane in 10 ml of tetrahydrofuran at room temperature,and the mixture was heated under reflux for 5-6 hours. The reactionsolution was poured onto ice-water and extracted several times withether. The combined organic phases were dried with sodium sulfate andevaporated, and the residue was dried under an oil-pump vacuum. Theresidue was chromatographed on 300 g of silica gel 60. With a mobilephase mixture of hexane/3% ethyl acetate, 500 g of unreacted startingmaterial 20a/20b were able to be eluted first. The ligand system 21 thenfollowed with the same mobile phase. After the solvent had been strippedoff, this ligand system was able to be crystallized by stirring withhexane. The yield was 1.7 g (34% with respect to Si, or 44% with respectto the 20a/20b reacted).

¹ H-NMR spectrum (100 MHz, CDCl₃): diastereomers (1:1) 7.2-8.2 (m), 4.05(s), 2.45 (d), 2.35 (d), -0.22 (s), -0.32 (s), -0.35 (s).

Mass spectrum: 416 M⁺, correct disintegration pattern and isotopepattern.

EXAMPLE Z Rac-Dimethylsilanediylbis(2-Methyl-4,5-Benzoindenyl)ZirconiumDichloride (22)

4.0 ml (10.2 mmol) of a 2.5 M butyllithium solution in hexane were addedto a solution of 1.7 g (4.1 mmol) of the ligand system 21 in 20 ml oftetrahydrofuran at room temperature under Ar as the inert gas, and themixture was stirred at room temperature for 14 hours. The residue whichremained after the solvent had been stripped off was dried under anoil-pump vacuum and washed with hexane. The pale brown powder thusobtained was dried under an oil-pump vacuum at 40-50° C. for severalhours, and added to a suspension of 1.0 g (4.0 mmol) of zirconiumtetrachloride in 25 ml of methylene chloride at -78° C. After themixture had been warmed to room temperature, the solvent was strippedoff and the residue was extracted with 20 ml of toluene in order toremove the meso form of the zirconocene 22. The residue of the tolueneextract was then extracted with 40 ml of methylene chloride. Thesolution was concentrated to a small volume and left to crystallize at-35° C. A total of 970 mg (42%) of the zirconocene 22 were able to beisolated as the pure racemate in several fractions.

¹ H-NMR spectrum of the racemate (300 MHz, CDCl₃): 7.96 (2,m), 7.78(2,m), 7.60 (2,d), 7.48-7.56 (4,m), 7.36 (2,d), 7.27 (2,s,β-Ind-H), 2.37(6,s,Ind-CH₃), 1.36 (6,s,Si--CH₃). Mass spectrum: 574 M⁺, correctdisintegration, correct isotope pattern.

EXAMPLE AA 2-Methyl-α-Acenaphthindan-1-One (23)

29.7 g (129 mmol) of 2-bromoisobutyryl bromide were added to a solutionof 20 g (129 mmol) of α-acenaphthene in 320 ml of methylene chloride atroom temperature. 43.5 g (324 mmol) of AlCl₃ were then added via asolids metering funnel in the course of 15 minutes. After the mixturehad been stirred for 30 minutes, it was poured into ice-water andextracted with methylene chloride. The organic phase was washed withwater and an NaHCO₃ solution, and dried with Na₂ SO₄. The residue whichremained after the solvent had been stripped off was filtered over ashort column with silica gel. 25 g (87%) of the indanone 23 wereobtained with hexane/ethyl acetate (9:2).

¹ H-NMR (CDCl₃, 100 MHz): 8.57 (d,₁), 7.60 (t,₁), 7.35 (d,₁), 7.25(s,1), 3.45 (q,₁), 3.40 (s,4), 2.60-2.95 (m,2), 1.35 (d,3).

EXAMPLE BB 2-Methyl-α-Acenaphthindene (24)

A solution of 20 g (90 mmol) of the compound 23 in 250 ml of atetrahydrofuran/methanol mixture (2:1) was added dropwise to asuspension of 3.8 g (100 mmol) of NaBH₄ in 80 ml of tetrahydrofuran. Themixture was stirred at room temperature for 2 hours, and 100 ml of ethylacetate and 100 ml of half-concentrated HCl were added. The mixture washeated under reflux for 10 minutes and extracted with ethyl acetate. Theorganic phase was washed with water and dried with Na₂ SO₄. Onconcentration and cooling to -35° C., a total of 16.3 g (88%) of thecompound 24 crystallized in several fractions.

¹ H-NMR (CDCl₃, 100 MHz): 7.1-7.8 (m,4,aromatic-H), 6.97 (m,1,olefin-H),3.37 (s,6,CH₂), 2.25 (d,3,CH₃).

EXAMPLE CC Dimethylbis(2-Methyl-α-Acenaphthindenyl)Silane (25)

10.8 g (52.4 mmol) of the compound 24 were deprotonated analogously toExample O and reacted with dimethyldichlorosilane. The organic phase wasevaporated and the residue was chromatographed on silica gel. 6.2 g(51%) of the ligand system 25 were able to be obtained with hexane/4%ethyl acetate.

¹ H-NMR (CDCl₃, 100 MHz): diastereomer pair 7.1-7.8 (m,aromatic-H), 4.0(s,CH), 3.45 (s,CH₂), 2.47 (d,CH₃), 2.40 (d,CH₃), -0.25 (s,SiCH₃), -0.35(s,SiCH₃), -0.37 (s,SiCH₃).

Example DDRac-Dimethylsilanediylbis(2-Methyl-α-Acenaphthindenyl)ZirconiumDichloride (26)

4.9 g (10.5 mmol) of the ligand system 25 were reacted analogously toExample P. The crude product, comprising the racemic form with the mesoform in a ratio of 1:1, was recrystallized from chloroform. 1.3 g (20%)of the racemate 26 were obtained in the form of an orange-yellow powder.

¹ H-NMR (CDCl₃, 100 MHz): 7.0-7.8 (m,aromatic-H), 3.1-3.4 (m,CH₂), 2.35(s,CH₃), 1.35 (s,SiCH₃).

Polymerization examples Example 1

A dry 24 dm³ reactor was flushed with propylene and filled with 12 dm³of liquid propylene. 35 cm³ of a toluene solution of methylaluminoxane(corresponding to 52 mmol of Al, average degree of oligomerization p=20)were then added and the batch was stirred at 30° C. for 15 minutes.

In parallel, 3.5 mg (0.005 mmol) ofrac-dimethylsilyl(2-methyl-4,6-diisopropyl-1-indenyl)₂ zirconiumdichloride were dissolved in 13.5 cm³ of a toluene solution ofmethylaluminoxane (20 mmol of Al) and preactivated by being left tostand for 15 minutes.

The wine-red solution was then introduced into the reactor, the mixturewas heated to 75° C. (10° C./minute) by supplying heat, and thepolymerization system was kept at 70° C., by cooling, for 1 hour. Thepolymerization was stopped by gassing off the excess monomer. 2.11 kg ofpolypropylene were obtained.

The activity of the metallocene was thus 603 kg of polypropylene/g ofmetallocene×hour.

Viscosity number=259 cm³ /g, M_(w) =305,000 g/mol; M_(w) /M_(n) =2.0;isotactic index=96.0%; bulk density=400 g/dm³ ; melt flow index(230/5)=8.5 dg/minute.

Comparison Example 1

Example 1 was repeated with the metallocenerac-dimethylsilyl(2-methyl-1-indenyl)₂ zirconium dichloride. Themetallocene activity was 395 kg of polypropylene/g of metallocene×hour.

Viscosity number=159 cm³ /g, M_(w) =158,000 g/mol; M_(w) /M_(n) =2.1 andthe melt flow index (230/5) was 48 dg/minute. The isotactic index (II)was 96.0%.

Comparison Example 2

Example 1 was repeated with the metallocenerac-dimethylsilyl(2-methyl-4-isopropyl-1-indenyl)₂ zirconium dichloride.

The metallocene activity was 460 kg of polypropylene/g ofmetallocene×hour, viscosity number=152 cm³ /g, M_(w) =147,500 g/mol,M_(w) /M_(n) =2.3 and melt flow index (230/5)=51 dg/minute.

Comparison Example 3

Example 1 was repeated with rac-dimethylsilyl(1-indenyl)₂ zirconiumdichloride. The metallocene activity was 695 kg of polypropylene/g ofmetallocene×hour.

Viscosity number=31 cm³ /g, M_(w) =18,500 g/mol, M_(w) /M_(n) =2.2, meltflow index (230/5) was no longer measurable.

Comparison Example 4

Example 1 was repeated with the metallocenerac-dimethylsilyl(4,7-dimethyl-1-indenyl)₂ zirconium dichloride. Themetallocene activity was 195 kg of polypropylene/g of metallocene×hour,viscosity number=16 cm³ /g, M_(w) =9,500 g/mol, M_(w) /M_(n) =2.0,II=87%, the melt flow index (230/5) was not measurable.

The four comparison experiments show that polypropylenes prepared withthe metallocenes substituted in various ways on the indenyl ligand andprepared with the unsubstituted metallocene show significant differencesin molecular weight. Including the metallocene according to theinvention from Example 1, the range extends from the wax range(Comparison Example 4) to the very high molecular weight polymeraccording to the invention (Example 1).

These experiments demonstrate the superiority of the metallocenessubstituted in the 2,4,6-position.

We claim:
 1. A compound of the formula VI ##STR11## in which M¹ istitanium, zirconium, hafnium, vanadium, niobium or tantalum, R¹, R², R⁴and R⁵ are identical or different and are hydrogen; (C₁ -C₂₀)alkyl; (C₆-C₁₄)aryl;(C₁ -C₁₀)fluoroalkyl; (C₆ -C₁₀)halogenoaryl; (C₂ -C₁₀)alkynyl;a radical --SiR⁶ ₃, in which R⁶ is (C₁ -C₁₀)alkyl; a halogen atom; or ahetero-aromatic radical which has 5 or 6 ring members and can containone or more hetero atoms, or adjacent radicals R¹ -R⁴, with the atomsjoining them, form one or more rings, R⁷ is a radical ##STR12## in whichM² is carbon, silicon, germanium or tin R⁸ and R⁹ are identical ordifferent and are hydrogen, (C₁ -C₂₀)alkyl, (C₆ -C₁₄)aryl, (C₁-C₁₀)alkoxy, (C₂ -C₁₀)alkenyl, (C₇ -C₂₀)arylalkyl, (C₇ -C₂₀)alkylaryl,(C₆ -C₁₀)aryloxy, (C₁ -C₁₀)fluoroalkyl, (C₆ -C₁₀)halogenoaryl, (C₂-C₁₀)alkynyl or halogen or R⁸ and R⁹, together with the atom joiningthem, form a ring, p is 0, 1, 2 or 3 and R¹⁰ and R¹¹ are identical ordifferent and are hydrogen, (C₁ -C₁₀)alkyl, (C₁ -C₁₀)alkoxy, (C₆-C₁₀)aryl, (C₆ -C₁₀)aryloxy, (C₂ -C₁₀)alkenyl, (C₇ -C₄₀)arylalkyl, (C₇-C₄₀)alkylaryl, (C₈ -C₄₀)arylalkenyl, hydroxyl or a halogen atom, andthe indenyl radicals in formula VI are substituted in the 2,6-; 2,4,6-;2,4,5-; 2,4,5,6- or 2,4,5,6,7-position.
 2. The compound as claimed inclaim 1, wherein M¹ is zirconium; and R¹⁰ and R¹¹ are chlorine.
 3. Thecompound as claimed in claim 1, wherein R² -R⁴, with the atoms joiningthem form one or more rings.
 4. The compound as claimed in claim 1,wherein R¹, R², R³ and R⁴ are identical or different and are hydrogen,(C₁ -C₁₀)alkyl, (C₆ -C₁₄)aryl, (C₁ -C₄)alkoxy, (C₂ -C₆)alkenyl, (C₁-C₆)fluoroalkyl, a halogen or a hetero-aromatic radical which has 5 or 6ring members and optionally contains one or more hetero atoms and R⁵ is(C₁ -C₁₀)alkyl, or adjacent radicals R² -R⁴, with the atoms joining themform a ring and M² is silicon.
 5. A compound of the formula VI ##STR13##in which M¹ is titanium, zirconium, hafnium, vanadium, niobium ortantalum, R¹, R², R³, and R⁴ are identical or different and arehydrogen; (C₁ -C₂₀)alkyl; (C₆ -C₁₄)aryl; (C₁ -C₁₀ )alkoxy; (C₂-C₁₀)alkenyl; (C₇ -C₂₀)arylalkyl; (C₇ -C₂₀)alkylaryl; (C₆ -C₁₀)aryloxy;(C₁ -C₁₀)fluoroalkyl; (C₆ -C₁₀)halogenoaryl; (C₂ -C₁₀)alkynyl; a radical--SiR⁶ ₃, in which R⁶ is (C₁ -C₁₀)alkyl; a halogen atom; or ahetero-aromatic radical which has 5 or 6 ring members and can containone or more hetero atoms, or adjacent radicals R¹ -R⁴, with the atomsjoining them, form one or more rings,R⁵ is (C₁ -C₂₀)alkyl; (C₆-C₁₄)aryl; (C₁ -C₁₀)alkoxy; (C₂ -C₁₀)alkenyl; (C₇ -C₂₀)arylalkyl; (C₇-C₂₀)alkylaryl; (C₆ -C₁₀)aryloxy; (C₁ -C₁₀)fluoroalkyl; (C₆-C₁₀)halogenoaryl; (C₂ -C₁₀)alkynyl; a radical --SiR⁶ ₃, in which R⁶ is(C₁ -C₁₀)alkyl; a halogen atom; or a hetero-aromatic radical which has 5or 6 ring members and can contain one or more hetero atoms, R⁷ is aradicalin which ##STR14## M² is carbon, silicon, germanium or tin R⁸ andR⁹ are identical or different and are hydrogen, (C₁ -C₂₀)alkyl, (C₆-C₁₄)aryl, (C₁ -C₁₀)alkoxy, (C₂ -C₁₀)alkenyl, (C₇ -C₂₀)arylalkyl, (C₇-C₂₀)alkylaryl, (C₆ -C₁₀)aryloxy, (C₁ -C₁₀)fluoroalkyl, (C₆-C₁₀)halogenoaryl, (C₂ -C₁₀)alkynyl or halogen or R⁸ and R⁹, togetherwith the atom joining them, form a ring, p is 0, and R¹⁰ and R¹¹ areidentical or different and are hydrogen, (C₁ -C₁₀)alkyl, (C₁-C₁₀)alkoxy, (C₆ -C₁₀)aryl, (C₆ -C₁₀)aryloxy, (C₂ -C₁₀)alkenyl, (C₇-C₄₀)arylalkyl, (C₇ -C₄₀)alkylaryl, (C₈ -C₄₀)arylalkenyl, hydroxyl or ahalogen atom.
 6. The compound as claimed in claim 5, whereinM¹ iszirconium, R¹⁰ and R¹¹ are chlorine, R¹, R², R³ and R⁴ are identical ordifferent and are hydrogen, (C₁ -C₁₀)alkyl, (C₆ -C₁₄)aryl, (C₁-C₄)alkoxy, (C₂ -C₆)alkenyl, (C₁ -C₆)fluoroalkyl, a halogen or ahetero-aromatic radical which has 5 or 6 ring members and optionallycontains one or more hetero atoms or adjacent radicals R¹ -R⁴, with theatoms joining them form a ring, R⁵ is (C₁ -C₁₀)alkyl, and M² is silicon.7. The compound as claimed in claim 6, wherein R¹ -R⁴, with the atomsjoining them form one or more rings.
 8. A compound of the formula VI##STR15## in which M¹ is titanium, zirconium, hafnium, vanadium, niobiumor tantalum, R¹ is (C₁ -C₂₀)alkyl; (C₆ -C₁₄)aryl; (C₁ -C₁₀)alkoxy; (C₂-C₁₀)alkenyl; (C₇ -C₂₀)arylalkyl; (C₇ -C₂₀)alkyaryl; (C₆ -C₁₀)aryloxy;(C_(1-C) ₁₀)fluoroalkyl; (C₆ -C₁₀)halogenoaryl; (C₂ -C₁₀)alkynyl; aradical --SiR⁶ ₃, in which R⁶ is (C₁ -C₁₀)alkyl; a halogen atom; or ahetero-aromatic radical which has 5 or 6 ring members and can containone or more hetero atoms,R², R³ and R⁴ are identical or different andare hydrogen; (C₁ -C₂₀ )alkyl; (C₆ -C₁₄)aryl; (C₁ -C₁₀)alkoxy; (C₂-C₁₀)alkenyl; (C₇ -C₂₀)arylalkyl; (C₇ -C₂₀)alkylaryl; (C₆ -C₁₀)aryloxy;(C₁ -C₁₀)fluoroalkyl; (C₆ -C₁₀)halogenoaryl; (C₂ -C₁₀)alkynyl; a radical--SiR⁶ ₃, in which R⁶ is (C₁ -C₁₀)alkyl; a halogen atom; or ahetero-aromatic radical which has 5 or 6 ring members and can containone or more hetero atoms, or adjacent radicals R¹ -R⁴, with the atomsjoining them, form one or more rings, R⁵ is hydrogen, R⁷ is a radical##STR16## in which M² is carbon, silicon, germanium or tin R⁸ and R⁹ areidentical or different and are hydrogen, (C₁ -C₂₀)alkyl, (C₆ -C₄)aryl,(C₁ -C₁₀)alkoxy, (C₂ -C₁₀)alkenyl, (C₇ -C₂₀)arylalky, (C₇-C₂₀)alkylaryl, (C₆ -C₁₀)aryloxy, (C₁ -C₁₀)fluoroalkyl, (C₆-C₁₀)halogenoaryl, (C₂ -C₁₀)alkynyl or halogen or R⁸ and R⁹, togetherwith the atom joining them, form a ring, p is 1 or 3, and R¹⁰ and R¹¹are identical or different and are hydrogen, (C₁ -C₁₀)alkyl, (C₁-C₁₀)alkoxy, (C₆ -C₁₀)aryl, (C₆ -C₁₀)aryloxy, (C₂ -C₁₀)alkenyl, (C₇-C₄₀)arylalkyl, (C₇ -C₄₀)alkyl, (C₈ -C₄₀)arylalkenyl, hydroxyl or ahalogen atom.
 9. The compound as claimed in claim 8, whereinM¹ iszirconium, R¹⁰ and R¹¹ are chlorine, R¹ is (C₁ -C₁₀)alkyl, (C₆-C₁₄)aryl, (C₁ -C₄)alkoxy, (C₂ -C₆)alkenyl, (C₁ -C₆)fluoroalkyl, ahalogen or a hetero-aromatic radical which has 5 or 6 ring members andoptionally contains one or more hetero atoms, R², R³ and R⁴ areidentical or different and are hydrogen, (C₁ -C₁₀)alkyl, (C₆ -C₄)aryl,(C₁ -₄)alkoxy, (C₂ -C₆)alkenyl, (C₁ -C₆)fluoroalkyl, a halogen or ahetero-aromatic radical which has 5 or 6 ring members and optionallycontains one or more hetero atoms or adjacent radicals R¹ -R⁴, with theatoms joining them form a ring, and M² is silicon.
 10. A compound of theformula VI ##STR17## in which M¹ is titanium, zirconium, hafnium,vanadium, niobium or tantalum, R¹, R³ and R⁴ are identical or differentand are hydrogen; (C₁ -C₂₀)alkyl; (C₆ -C₁₄)aryl; (C₁ -C₁₀)alkoxy; (C₂-C₁₀)alkenyl; (C₇ -C₂₀)arylalkyl; (C₇ -C₂₀)alkylaryl; (C₆ -C₁₀ )aryloxy;(C₁ -C₁₀)fluoroalkyl; (C₆ -C₁₀)halogenoaryl; (C₂ -C₁₀)alkynyl; a radical--SiR⁶ ₃, in which R⁶ is (C₁ -C₁₀)alkyl; a halogen atom; or ahetero-aromatic radical which has 5 or 6 ring members and can containone or more hetero atoms, or adjacent radicals R¹ -R⁴, with the atomsjoining them, form one or more rings,R² is (C₁ -C₂₀)alkyl; (C₆-C₁₄)aryl; (C₁ -C₁₀)alkoxy; (C₂ -C₁₀)alkenyl; (C₇ -C₂₀)arylalkyl; (C₇-C₂₀)alkylaryl; (C₆ -C₁₀)aryloxy; (C₁ -C₁₀)fluoroalkyl; (C₆-C₁₀)halogenoaryl; (C₂ -C₁₀)alkynyl; a radical --SiR⁶ ₃, in which R⁶ is(C₁ -C₁₀)alkyl; a halogen atom; or a hetero-aromatic radical which has 5or 6 ring members and can contain one or more hetero atoms, R⁵ ishydrogen, R⁷ is a radical ##STR18## in which M² is carbon, silicon,germanium or tin R⁸ and R⁹ are identical or different and are hydrogen,(C₁ -C₂₀)alkyl, (C₆ -C₁₄)aryl, (C₁ -C₁₀)alkoxy, (C₂ -C₁₀)alkenyl, (C₇-C₂₀)arylalkyl, (C₇ -C₂₀)alkylaryl, (C₆ -C₁₀)aryloxy, (C₁-C₁₀)fluoroalkyl, (C₆ -C₁₀)halogenoaryl, (C₂ -C₁₀)alkynyl or halogen orR⁸ and R⁹, together with the atom joining them, form a ring, is 1 or 3,and R¹⁰ and R¹¹ are identical or different and are hydrogen, (C₁-C₁₀)alkyl, (C₁ -C₁₀)alkoxy, (C₆ -C₁₀)aryl, (C₆ -C₁₀)aryloxy, (C₂-C₁₀)alkenyl, (C₇ -C₄₀)arylalkyl, (C₇ -C₄₀)alkylaryl, (C₈-C₄₀)arylalkenyl, hydroxyl or a halogen atom.
 11. The compound asclaimed in claim 10, whereinM¹ is zirconium, R¹⁰ and R¹¹ are chlorine,R¹, R³, and R⁴ are identical or different and are hydrogen, (C₁-C₁₀)alkyl, (C₆ -C₄)aryl, (C₁ -C₄)alkoxy, (C₂ -C₆)alkenyl, (C₁-C₆)fluoroalkyl, a halogen or a hetero-aromatic radical which has 5 or 6ring members and optionally contains one or more hetero atoms oradjacent radicals R¹ -R⁴, with the atoms joining them form a ring, R² is(C₁ -C₁₀)alkyl, (C₆ -C₁₄)aryl, (C₁ -C₄)alkoxy, (C₂ -C₆)alkenyl, (C₁-C₆)fluoroalkyl, a halogen or a hetero-aromatic radical which has 5 or 6ring members and optionally contains one or more hetero atoms, and M² issilicon.
 12. A compound of the formula VI ##STR19## in which M¹ istitanium, zirconium, hafnium, vanadium, niobium or tantalum,R¹, R² andR⁴ are identical or different and are hydrogen; (C₁ -C₂₀)alkyl; (C₆-C₁₄)aryl; (C₁ -C₁₀)alkoxy; (C₂ -C₁₀)alkenyl; (C₇ -C₂₀)arylalkyl; (C₇-C₂₀)alkylaryl; (C₆ -C₁₀)aryloxy; (C₁ -C₁₀)fluoroalkyl; (C₆-C₁₀)halogenoaryl; (C₂ -C₁₀)alkynyl; a radical --SiR⁶ ₃, in which R⁶ (C₁-C₁₀)alkyl; a halogen atom; or a heteroaromatic radical which has 5 or 6ring members and can contain one or more hetero atoms, or adjacentradicals R¹ -R⁴, with the atoms joining them, form one or more rings, R³is (C₁ -C₂₀)alkyl; (C₆ -C₁₄)aryl; (C₁ -C₁₀)alkoxy; (C₂ -C₁₀)alkenyl; (C₇-C₂₀)arylalkyl; (C₇ -C₂₀)alkylaryl; (C₆ -C₁₀)aryloxy; (C_(1-C)₁₀)fluoroalkyl; (C₆ -C₁₀)halogenoaryl; (C₂ -C₁₀)alkynyl; a radical--SiR⁶ ₃, in which R⁶ is (C₁ -C₁₀)alkyl; a halogen atom; or ahetero-aromatic radical which has 5 or 6 ring members and can containone or more hetero atoms, R⁵ is hydrogen, R⁷ is a radical ##STR20## inwhich M² is carbon, silicon, germanium or tin R⁸ and R⁹ are identical ordifferent and are hydrogen, (C₁ -C₂₀)alkyl, (C₆ -C₁₄)aryl, (C₁-C₁₀)alkoxy, (C₂ -C₁₀)alkenyl, (C₇ -C₂₀)arylalkyl, (C₇ -C₂₀)alkylaryl,(C₆ -C₁₀)aryloxy, (C₁ -C₁₀)fluoroalkyl, (C₆ -C₁₀)halogenoaryl, (C₂-C₁₀)alkynyl or halogen or R⁸ and R⁹, together with the atom joiningthem, form a ring, p is 1 or 3, and R¹⁰ and R¹¹ are identical ordifferent and are hydrogen, (C₁ -C₁₀)alkyl, (C₁ -C₁₀)alkoxy, (C₆-C₁₀)aryl, (C₆ -C₁₀)aryloxy, (C₂ -C₁₀)alkenyl, (C₇ -C₄₀)arylalkyl, (C₇-C₄₀)alkylaryl, (C₈ -C₄₀)arylalkenyl, hydroxyl or a halogen atom. 13.The compound as claimed in claim 12, whereinM¹ is zirconium, R¹⁰ and R¹¹are chlorine, R¹, R² and R⁴ are identical or different and are hydrogen,(C₁ -C₁₀)alkyl, (C₆ -C₁₄)aryl, (C₁ C₄)alkoxy, (C₂ -C₆)alkenyl, (C₁-C₆)fluoroalkyl, a halogen or a hetero-aromatic radical which has 5 or 6ring members and optionally contains one or more hetero atoms oradjacent radicals R¹ -R⁴, with the atoms joining them form a ring, R³ is(C₁ -C₁₀)alkyl, (C₆ -C₁₄)aryl, (C₁ -C₄)alkoxy, (C₂ -C₆)alkenyl, (C₁-C₆)fluoroalkyl, a halogen or a hetero-aromatic radical which has 5 or 6ring members and optionally contains one or more hetero atoms, and M² issilicon.
 14. A compound of the formula VI ##STR21## in which M¹ istitanium, zirconium, hafnium, vanadium, niobium or tantalum,R¹, R² andR³ are identical or different and are hydrogen; (C₁ -C₂₀)alkyl; (C₆-C₁₄)aryl; (C₁ -C₁₀)alkoxy; (C₂ -C₁₀)alkenyl; (C₇ -C₂₀)arylalkyl; (C₇-C₂₀)alkylaryl; (C₆ -C₁₀)aryloxy; (C₁ -C₁₀)fluoroalkyl; (C₆-C₁₀)halogenoaryl; (C₂ -C₁₀)alkynyl; a radical --SiR⁶ ₃, in which R⁶ is(C₁ C₁₀)alkyl; a halogen atom; or a hetero-aromatic radical which has 5or 6 ring members and can contain one or more hetero atoms, or adjacentradicals R¹ -R⁴, with the atoms joining them, form one or more rings, R⁴is (C₁ -C₂₀)alkyl; (C₆ -C₄)aryl; (C₁ -C₁₀)alkoxy; (C₂ -C₁₀)alkenyl; (C₇-C₂₀)arylalkyl; (C₇ -C₂₀)alkylaryl; (C₆ -C₁₀)aryloxy; (C₁-C₁₀)fluoroalkyl; (C₆ -C₁₀)halogenoaryl; (C₂ -C₁₀)alkynyl; a radical--SiR⁶ ₃, in which R⁶ is (C₁ -C₁₀)alkyl; a halogen atom; or ahetero-aromatic radical which has 5 or 6 ring members and can containone or more hetero atoms, R⁵ is hydrogen, R⁷ is a radical ##STR22## inwhich M² is carbon, silicon, germanium or tin R⁸ and R⁹ are identical ordifferent and are hydrogen, (C₁ -C₂₀)alkyl, (C₆ -C₁)aryl, (C₁-C₁₀)alkoxy, (C₂ -C₁₀)alkenyl, (C₇ -C₂₀)arylalkyl, (C₇ -C₂₀)alkylaryl,(C₆ -C₁₀)aryloxy, (C₁ -C₁₀)fluoroalkyl, (C₆ -C₁₀)halogenoaryl, (C₂-C₁₀)alkynyl or halogen or R⁸ and R⁹, together with the atom joiningthem, form a ring, p is 1 or 3, and R¹⁰ and R¹¹ are identical ordifferent and are hydrogen, (C₁ -C₁₀)alkyl, (C₁ -C₁₀)alkoxy, (C₆-C₁₀)aryl, (C₆ -C₁₀)aryloxy, (C₂ -C₁₀)alkenyl, (C₇ -C₄₀)arylalkyl, (C₇-C₄₀)alkylaryl, (C₈ -C₄₀)arylalkenyl, hydroxyl or a halogen atom. 15.The compound as claimed in claim 14, whereinM¹ is zirconium, R¹⁰ and R¹¹are chlorine, R¹, R² and R³ are identical or different and are hydrogen,(C₁ -C₁₀)alkyl, (C₆ -C₁₄)aryl, (C₁ -C₄)alkoxy, ((C₂ -C₆)alkenyl, (C₁-C₆)fluoroalkyl, a halogen or a hetero-aromatic radical which has 5 or 6ring members and optionally contains one or more hetero atoms oradjacent radicals R¹ -R⁴, with the atoms joining them form a ring, R⁴ is(C₁ -C₁₀)alkyl, (C₆ -C₁₄)aryl, (C₁ -C₄)alkoxy, (C₂ -C₆)alkenyl, (C₁-C₆)fluoroalkyl, a halogen or a hetero-aromatic radical which has 5 or 6ring members and optionally contains one or more hetero atoms, and M² issilicon.